Examples

Ruby Logging Setup

Setting Up Logging

Ruby logging setup with Logger logs requests and errors.

Introduction to Ruby Logger

Ruby's standard library provides a powerful logging utility named Logger. It allows developers to record and manage application logs effectively, providing insights into application behavior, errors, and other significant events. In this guide, we'll explore how to set up and use Logger in a Ruby application.

Installing Logger

The Logger class is part of Ruby's standard library, so you don't need to install any external gems to use it. You can start using it by requiring it in your Ruby script:

Basic Logger Setup

Setting up a basic logger is straightforward. You can create a new logger instance and specify an output destination, such as STDOUT or a file. Here's an example of setting up a logger to log messages to the console:

In the above code, we create a new Logger instance that outputs to the console. We also set the logging level to DEBUG, which means all messages with severity levels of DEBUG and above will be logged.

Logging to a File

For persistent logs, you can configure the logger to write to a file. This is useful for tracking issues over time. Here's how you can set up file logging:

The above code will create or append logs to a file named application.log. The logging level is set to INFO, so only messages with severity levels of INFO and above will be logged.

Logging Different Severity Levels

Ruby's Logger provides several severity levels: DEBUG, INFO, WARN, ERROR, and FATAL. You can use these levels to categorize your logs:

By using different severity levels, you can filter and manage logs more effectively. Each method corresponds to a different severity level, allowing you to control the granularity of your log output.

Formatting Log Output

Logger allows customization of log output format using formatters. You can define a custom format to include timestamps, log levels, and messages:

The above code snippet sets a custom formatter for the logger. This formatter includes the datetime, severity, and the log message in each log entry.

Examples

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